202 A Grammar of Spoken English Discourse
another increment which they felt necessary for the production of their
target state, see Chapter 5 examples (5) and (6).
Brazil’s claim that speakers tell or ask based upon their assumption of the
extent of shared speaker/hearer understanding was shown, like all theories
predicated on the concept of shared knowledge, in Chapter 3 to be both
psychologically problematic and nebulous. Adoption of Sperber and
Wilson’s concept of cognitive environments, however, ensured that Brazil’s
insightful recognition that speakers frame their messages on the basis of
their moment by moment understanding of the state of speaker/hearer
convergence was rendered psychologically feasible and operationally trans-
parent. Instead of making assumptions as to the state of speaker/hearer
understanding, speakers gauge their contributions to the discourse and
decide if they should tell or ask based upon the state of their individual
cognitive environments. They form their assessments of what needs to be
told based upon their own perceptual abilities, their previous experiences
and memories of deriving information from the environment and from any
inferences arising from their perceptions, experiences and memories.
The literature review in Chapter 3 demonstrated that the four premises
which underpin Brazil’s grammar of used language are all supported.
Brazil’s claim that language is a purposeful, interactive, cooperative hap-
pening which can be interpreted as it unfolds in increments appears sound.
Objections that linear grammars are incapable of describing all the possible
sentences of the language were shown in Chapter 4 not to apply to a
grammar which described used language. However, Brazil’s claim that
used language consists solely of end-rising and end-falling tones was shown
to be in need of some reworking. Tench’s (1997, 2003) claim, that some
instances of level tone label speakers’ contribution to the discourse as self
evident, was supported in the data. As a result Brazil’s description of used
language has been extended to include speaker selection of level tone when
they project their contribution to the discourse as self-evident.
Numerous scholars, though not Brazil have argued that the position where
a tone occurs in an utterance determines its communicative signifi cance.
For example Crystal (1975) argues that tones only contribute an independent
meaning when they are not the tones that are expected. He argues that it
is only in the 20 per cent of cases where an utterance is completed with a
non-falling tone that the ‘unexpected’ non-falling tone signals additional
communicative value. Seventy-seven per cent of increments identifi ed within
the corpus examined here were completed by an end-falling tone. We have
seen that increment fi nal rises add extra communicative value to increments
by deferring to the hearer, by emphasizing the state of speaker/hearer